Improvement in steam-engine rotary valves



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weessaeew gaat@ A. R. UFFINGTON, OF UNITED STATES ARMY.

Letters Patent No. 87,538, lated Mei/rch 9, 1869.

The Schedule referred to in these Letters Patent and making part of thesame.

To all whom 'itma-y concerm' Be it known that I, A. R. BmrFrNeTomcaptainof ordnance, and brevet maior, United States army, have invented a newand useful Improved `Valve, for use in and with steam and other engines,viz, a revolving valve, that can` be adjusted to out oli and 1ead,

'at will, the exhaust fully opening before, and closing slower than theportg and I vdoiherehy declare that the following is a fullclear, andexact description of th-construction and operation of the same,referencebeing' had to the annexed drawings, forming part of thisspecification, lin which- Figure 1 is' a plane view of valve, and

v Figures 2, 3, 4, and 5, plane views of parts of valve and valve-seat.

The valve consists essentially of a plate, e, iig. 1, fastened to anarbor `or shaft-c, fig. 1, so as t'o revolve with it, and having twoconcentric annular slots d e, as shown in fig. 1.

Between these slots, on eachside of the valve-plate, an annularspring-packing, l, iig.1, is p'laced, in a groove of rectangularcross-section.

`Inside of this groove, on each face, a plate is embedded. These platesare shown in F, fig. 3, and G, iig. 4. One of' these, F, tlg. 3, has asleeve, 7i, shown in section h, fig. y5, through which the shaft orarbor turning the valve passes. l

These two plates, F and Gr, iigs. 3 and 4, constitute the cuttingeoii,arrangement, or device, and on the valve are connected, by a pin orbolt, i, figs. 3 and 4, whose position, when theport is open throughoutthe whole-stroke, is shown at b, iig. 1.

nt, iig. 2, represents the valve-seat. The four holes, :n x, y y, are,the inside ones, :c 11:, the ports, and the outside ones, y y, theexhaust; one of each connected, as below indicated, with the top andbottom, or ends, of the steam or other cylinder.

Passing between the ports andV exhausts, as shown in the fig. 2, is anannular groove, Ic, oi' rectangular cross-section, corresponding, indistance from the com tre, to the annular packing on thefaee oi thevalveplate in contaetwith the seat.

The cover: of the valve corresponds exactly with the valve-seat, thegrooves and holes, ports and exhausts, being alike, and opposite.

The annular slots l c, fig. l, of the valveplatc, are

concentric with tliecentre, and so arranged that one exhaust-hole, andthe port farthest from it, are always open during the revolution of thevalve, `except at one point, viz, when the change to the other exhaustandf port-holes is about to take place. At this time, all are closed. 4

The valve-plate being adjusted to the shaft or arbor, so as tn permit itto be turned around the shaft or arbor, and fastened again Iat anypoint, the time of this changing, just named, from one port andexhausthole to the other set, may be made to correspond to 'any positionof the piston-head in the cylinder, and consequently the lead vcan beadjusted at will.

The sleeve It of the cut-olf plate, figs. 3 and 5, projecting on theshaft or arbor, through the valvecover, permits the cut-off device to beturned around it in one direction, and fastened again at any point,

Without removing the valve-cover; and thus for sta tionary, notreversible engines, the eut-off may be adjusted at will.

From the nature of the motion--angular-of the valve, and relativeposition of the port and .exhaustholes, their centres being in the'samestraight line, 1t follows, that the ports being nearer the centre ofinotion, will open slower than, and begin to close before lthe exhausts.

To pack the valve, besides having the parte all ground together, thesteam or other motor enters between the plates of the cut-od' device andthe valve- Vplate, the former being made suiiiciently thin to per-4mitsotne play between the valve-plate, and seat and cover; and in theannular grooves, in valve, and4 seat, and cover, as above described,annular springpackings are placed, which, also acted on by 'the motorentering the grooves, through connections, (grooves on valve-platefaces,) made at any point, as at Z, iig. 1, with the slot e, iig. 1,press outward, and pack hetween the ports and exhausts.

The relative position of the valve herein described, to the cylinder, isnot fixed; for instance, the valve may be placed on the crank-shaft,dispensing with the devices used to move the slide and rotating valve.Therefore,

What I claim as my invention, and desire to secure by Letters Patent,'is- The improved revolving valve, for steam and other engines,consisting of devices herein described, ern bracing the valve-plate e,with the two concentric circular slots el and e, and the groove 7c, forthe reception ofthe annular packing l, the cut-off` devices E and G,sleeve h, seat m, with its groove k, and ports y y and a: x, arranged tooperate substantially as herein set forth.

A. R. BUFFINGTN.

Witnesses: y

. Fianna H. Priirrs,

JOHN Arrnm.

